Analytics Test 2

The number of minutes that Samantha waits to catch the bus is uniformly distributed between 0 and 15 minutes. What is the probability that Samantha has to wait less than 4.5 minutes to catch the bus?

30%

stacked-column chart

allows the reader to compare the relative values of quantitative variables for the same category in a bar chart - mult variables

clustered-column (or bar) chart

an alternative chart to stacked column chart for comparing quantitative variables - mult variables

key performance indicators (KPIs)

automobile dashboard: current speed, fuel level, and oil pressure business dashboard: financial position, inventory on hand, customer service metrics

The charts that are helpful in making comparisons between categorical variables are

bar charts and column charts

In order to visualize three variables in a two-dimensional graph, we use a

bubble chart

parallel-coordinates plot

chart for examining data with more than two variables - includes a different vertical axis for each variable - each observation is represented by drawing a line on the parallel-coordinates plot connecting each vertical axis - the height of the line on each vertical axis represents the value taken by that observation for the variable corresponding to the vertical axis

A PivotChart, in few instances, is the same as a

clustered-column chart

pie chart

common form of chart used to compare categorical data

An experiment consists of determining the speed of automobiles on a highway by the use of radar equipment. The random variable in this experiment is a

continuous random variable

PivotTable

crosstabulation in Microsoft Excel

A two-dimensional graph representing the data using different shades of color to indicate magnitude is called a

heat map

An effective display of trend and magnitude is achieved by using a combination of a

heat map and sparklines

Data-ink is the ink used in a table or chart that

is necessary to convey the meaning of the data to the audience

The best way to differentiate chart elements is using

labels

A time series plot is also known as a

line chart

line chart

line that connects the points in the chart - useful for time series data collected over a period of time (mins, hours, days, years, etc)

variance

measure of variability

data-ink ratio

measures the proportion of what Tufte terms "data-ink" to the total amount of ink used in a table or chart

Probability is the

numerical measure of the likelihood that an event will occur

verification

process of determining that the computer procedure that performs the simulation calculations is logically correct - not complete until the user develops a high degree of confidence that the computer procedure is error free

validation

process of ensuring that the simulation model provides an accurate representation of a real system

random experiment

process that generates well-defined outcomes

risk analysis

quantifying the likelihood and magnitude of an undesirable outcome

In many cases, white space in a chart can improve

readability

A simulation model extends spreadsheet modeling by

replacing the use of single values for parameters with a range of possible values

The process of evaluating a decision in the face of uncertainty by quantifying the likelihood and magnitude of an undesirable outcome is known as

risk analysis

The event containing the outcomes belonging to A or B or both is the __________ of A and B.

union

bar charts

use horizontal bars to display the magnitude of the quantitative variable

column charts

use vertical bars to display the magnitude of the quantitative variable

exponential probability distribution

used for random variables like: - time between patient arrivals at an ER - distance between defects in a highway

crosstabulation

useful type of table for describing data of two variables

conditional probability

when the probability of one event is dependent on whether some related event has already occurred

To summarize and analyze data with both a crosstabulation and charting, Excel typically pairs

PivotCharts with PivotTables

Which one of the following statements is not true concerning PivotTables in Excel?

PivotTables can be built using data arrayed in rows

The __________ probability distribution can be used to estimate the number of vehicles that go through an intersection during the lunch hour.

Poisson

bubble chart

graphical means of visualizing 3 variables in a 2D graph that sometimes is a preferred alternative to a 3D graph

scatter chart

graphical presentation of the relationship between two quantitative variables

D and M are independent events

if the probability of event D is not changed by the existence of event M

Deleting the grid lines in a table and the horizontal lines in a chart

increases the data-ink ratio

data-ink

ink used in a table or chart that is necessary to convey the meaning of the data to the audience

non-data-ink

ink used in a table or chart that serves no useful purpose in conveying the data to the audience

The data dashboard for a marketing manager may have KPIs related to

current sales measures and sales by region

A disadvantage of stacked-column charts and stacked-bar charts is that

it can be difficult to perceive small differences in areas

In a business, the values indicating the business's current operating characteristics, such as its financial position, the inventory on hand, and customer service metrics, are typically known as

key performance indicators (KPI's)

expected value

mean of a random variable

A _____________ is a graphical presentation of the relationship between two quantitative variables.

scatter chart

A line chart that has no axes but is used to provide information on overall trends for time series data is called a

sparkline

To avoid problems in interpreting the differences in color in a heat map, ____________ can be added.

sparklines

sparkline

special type of line chart - minimalist type of line chart that can be placed directly into a cell in Excel - contains no axes; they display only the line for the data - takes up very little space and they can be effectively used to provide information on overall trends for time series data

Sample space is

the collection of all possible outcomes

All the events in the sample space that are not part of the specified event are called

the complement of the event

The center of a normal curve is

the mean of the distribution

Tables should be used instead of charts when

the values being displayed have different units or very different magnitudes

PivotChart

to summarize and analyze data with both a cross tabulation and charting, Excel pairs PivotCharts with PivotTables

A __________ is useful for visualizing hierarchical data along multiple dimensions.

treemap

A _____________ is a line that provides an approximation of the relationship between the variables.

trendline

_________ are visual methods of displaying data.

Charts

DJ needs to display data over time. Which of the following charts should he use?

Line chart

A ___________ uses repeated random sampling to represent uncertainty in a model representing a real system and that computes the values of model outputs.

Monte Carlo Simulation

In a normal distribution, which is greater, the mean or the median?

Neither the mean or the median (they are equal)

Which statement is true about mutually exclusive events?

If events A and B cannot occur at the same time, they are called mutually exclusive

Two events are independent if

P(A | B) = P(A) or P(B | A) = P(B)

geographical information system (GIS)

- a system that merges maps and statistics to present data collected over different geographical areas - helps in interpreting data and observing patterns

table design principles

- avoid using vertical lines in a table unless they are necessary for clarity - horizontal lines are generally necessary only for separating column titles from data values or when indicating that a calculation has taken place

data visualization involves

- creating a summary table for the data - generating charts to help interpret, analyze, and learn from the data

uses of data visualization

- helpful for identifying data errors - reduces the size of your data set by highlighting important relationships and trends in the data

tables should be used when

- the reader needs to refer to specific numerical values - the reader needs to make precise comparisons between different values and not just relative comparisons - the values being displayed have different units or very different magnitudes

What is the total area under the normal distribution curve?

1

A survey of 100 random high school students finds that 85 students watched the Super Bowl, 25 students watched the Stanley Cup Finals, and 20 students watched both games. How many students did not watch either game?

10

A health conscious student faithfully wears a device that tracks his steps. Suppose that the distribution of the number of steps he takes in a day is normally distributed with a mean of 10,000 and a standard deviation of 1,500 steps. What percent of the days does he exceed 13,000 steps?

2.28%

heat map

2D graphical representation of data that uses different shades of color to indicate magnitude

The random variable X is known to be uniformly distributed between 2 and 12. Compute E(X), the expected value of the distribution.

7

Which of the following is a disadvantage of using simulation?

Each simulation run provides only a sample of how the real system will operate

The software package most commonly used for creating simple charts is

Excel

Which of the following graphs cannot be used to display categorical data?

Scatter chart

__________ merges maps and statistics to present data collected over different geographies.

The geographic information system

Which of the following is not a characteristic of the normal probability distribution?

The standard deviation must be 1

__________ is the process of determining that a simulation model provides an accurate representation of a real system.

Validation

normal probability distribution

a continuous random variable with applications used for: - test scores - height and weights of people

Poisson Probability Distribution

a discrete random variable that is often useful in estimating the number of occurrences of an event over a specified interval of time or space

trendline

a line that provides an approximation of the relationship between two variables

probability

a numerical measure of the likelihood that an event will occur

discrete uniform probability distribution

a probability distribution for which each possible value of the random variable has the same probability

A chart that is recommended as an alternative to a pie chart is a

bar chart

A data visualization tool that updates in real time and gives multiple outputs is called

data dashboard

data-dashboard

data visualization tool that illustrates multiple metrics and automatically updates these metrics as new data become available

A variable that can only take on specific numeric values is called a

discrete random variable

uniform probability distribution

every interval of a given length being equally likely

Making visual comparisons between categorical variables may be difficult in a

pie chart

A __________ describes the range and relative likelihood of all possible values for a random variable.

probability distribution for a random variable

The outcome of a simulation experiment is a(n)

probability distribution for one or more output measures

realization

probability that is generated from observations

scatter-chart matrix

useful chart for displaying multiple variables

treemap

useful for visualizing hierarchical data along multiple dimensions

triangular probability distribution

useful only when subjective probability estimates are available

charts / graphs

visual methods of displaying data